【作者】 刘童鸽；

【导师】 李钢；

【作者基本信息】 大连理工大学 ， 工业催化， 2011， 硕士

【摘要】 随着全球经济的快速发展,水资源污染问题日益严重。在众多水污染中,重金属污染占了相当大的比例。重金属是一种危害巨大的污染物,它在生物体内长期积累,不易降解,产生的毒性严重危害到生态环境和人类生命健康。传统的重金属离子检测方法有原子吸收光谱法、原子发射光谱法、原子荧光光谱法和电感耦合等离子体—质谱法等,这些方法都存在样品预处理复杂、操作耗时、仪器昂贵等缺点,难以满足现场快速检测的要求。近年来,光化学传感器的研究受到了广泛关注,它作为一种新的重金属离子检测手段,具有不需要预处理、成本低、灵敏度高、选择性好等优点。作为光化学传感器载体的介孔分子筛具有比表面积大、孔道规则有序、表面带有羟基、合成工艺简单、热稳定性高等优点。将发光分子固载在介孔分子筛上制备出兼具发光分子及介孔分子筛二者优点的新型光化学传感器,可以满足实际重金属离子检测的需要。本文将发光分子4-(2-吡啶偶氮)间苯二酚(PAR)固载在经过氮位-三甲氧基硅基丙基-氮,氮,氮位-三甲基氯化铵(TMAC)功能化的介孔分子筛HMS上,制得一种新型的对重金属离子具有检测作用的光化学传感器HMS-TMAC-PAR。采用X射线衍射、傅里叶变换红外光谱、热重分析、元素分析、N2物理吸附和紫外可见漫反射光谱对此材料进行表征,并对材料的比色识别性质、选择性、灵敏性和重复使用性进行了研究。结果表明,在碱性条件下,HMS-TMAC-PAR对重金属离子具有选择性,Fe3+Cd2+Ni2+、Zn2+Pb2+Co2+Hg2+和Cu2+等重金属离子使HMS-TMAC-PAR水溶液的颜色从浅黄色变到橘黄色或是浅紫色；而在强酸性条件下,HMS-TMAC-PAR对Cu2+具有选择性,只有Cu2+使HMS-TMAC-PAR水溶液颜色发生变化。在pH=12时,HMS-TMAC-PAR对水中Cu2+具有较高的灵敏性,检测限可达0.81ppb,并且经过EDTA处理后可以重复使用。更多还原

【Abstract】 With the rapid development of the global economy, the problem of water pollution is growing severely. Heavy metals pollution takes a fairly large proportion on water pollution. Heavy metals, which are a great hazard of pollutants, can accumulate chronically in vivo and is not easy to be degraded. The toxicity of heavy metals severely endanger the ecological environment and human health. Conventional detection methods for heavy metal ions, including atomic absorption spectrometry (AAS), atomic emission spectrometry (AES), atomic fluorescence spectrometry (AFS) and inductively coupled plasma mass spectrometry (ICP-MS), etc, have disadvantages of sophisticated pretreatment procedures, time-consuming, expensive instruments and are difficult to meet the on-site requirement for rapid detection.In recent years, there has been growing interest in the development of optical chemosensor, as a new detection method for heavy metal ions, which has advantages of no pretreatment, low cost, high sensitivity and good selectivity. Mesoporous molecular sieves as the hosts of optical chemosensor have advantages of high surface areas, uniform pore size, surface with hydroxyl, simple synthesis and high thermal stability. The novel optical chemosensors based on luminescent molecules immobilizing on mesoporous molecular sieves have the advantages of both to meet the needs of practical detection for heavy metal ions.In this paper, a novel optical chemosensor (HMS-TMAC-PAR) for heavy metal ion detection had been prepared by immobilizing the luminescent molecule 4-(2-pyridylazo)resorcinol (PAR) on the functionalized HMS via N-trimethoxysilylpropyl-N,N,N-trimethylammonium chloride (TMAC). The successful fabrication of this material was confirmed by extensive characterizations using XRD, FT-IR, TG, elemental analysis, N2 physical adsorption and UV-vis, meanwhile its colorimetric properties, selectivity, sensitivity and reusability were also investigated. The results showed that HMS-TMAC-PAR responded selectively to heavy metal ions, such as Fe3+, Cd2+, Ni2+, Zn2+, Pb2+, Co2+, Hg2+and Cu2+with a color change from light yellow to orange or light purple in alkaline solutions, while under strongly acidic conditions HMS-TMAC-PAR responded selectively to Cu2+and showed a color change only for Cu2+. At pH 12, HMS-TMAC-PAR had a high sensitivity that maked it possible to detect Cu2+ in aqueous solution with a detection limit of 0.81 ppb and HMS-TMAC-PAR could be used repeatedly by treatment with a solution of EDTA.更多还原